1. Field of the Invention
The present invention relates to a hard disk drive (HDD), and more particularly, to an actuator of an HDD, which can improve a connection structure for the actuator and a flexible printed circuit and can reduce an electromagnetic interference (EMI) of a voice coil motor.
2. Description of Related Art
An HDD is one type of auxiliary memory device for a computer, which reproduces/records data from/on a disk by using a read/write head.
FIG. 1 is a schematic plan view of a conventional HDD, and FIG. 2 is an exploded perspective view of a conventional actuator.
Referring to FIGS. 1 and 2, the HDD includes at least one or more data storing disks 20, a spindle motor 30 installed on a base plate 10 to rotate the disk 20, and an actuator 40 having a read/write head 41 for reproducing/recording data from/on the disk 20.
The disks 20 are installed to be spaced apart from one another by a predetermined interval and to be rotatable by the spindle motor 30.
The actuator 40 is installed to be rotatable on a pivot 47 provided on the base plate 10. The actuator 40 has an actuator arm 46, and the actuator arm 46 has at its center portion a pivot hole 48 for rotatably connecting the actuator arm 46 to the pivot 47. A suspension 44 is installed at one end portion of the actuator arm 46 to elastically bias a slider 42 mounting the read/write head 41 toward a surface of the disk 20. A voice coil motor (VCM) 50 is provided in the actuator 40 to supply a driving force for rotating the actuator arm 46. The voice coil motor 50 has a VCM coil 56 connected to a rear end portion 57 of the actuator arm 46. A lower yoke 51 is fixedly installed on the base plate 10 under the VCM coil 56 to be spaced apart from the VCM coil 56 by a predetermined interval. An upper yoke 52 is installed over the VCM coil 56 and is connected to the lower yoke 51 with screws 59. Magnets 53 and 54 are respectively attached to the lower and upper yokes 51 and 52, and are respectively spaced apart from the VCM coil 56 by predetermined intervals.
In the so-constructed conventional HDD, during the data reproducing/recoding operation, a lift force caused by the rotation of the disk 20 and an elastic force due to the suspension 44 are applied to the slider 42 mounting the read/write head 41. Accordingly, the slider 42 maintains its lift state at a constant height from a data zone 22 of the disk 20 by a resultant force of the lift force and the elastic force, and the head 41 mounted on the slider 42 reproduces/records data from/on the disk 20 while maintaining a constant interval from the rotating disk 20.
In a small mobile HDD, a lead wire is soldered to the actuator arm 46, the method of which will now be described in detail with reference FIG. 3. However, this soldering method is difficult to be performed and may degrade the performance of the HDD due to a possible electrical short.
FIG. 3 is a plan view of a lead wire connected to an actuator arm of a conventional HDD, which is disclosed in U.S. Pat. No. 5,734,528.
Referring to FIG. 3, a lead wire 71 is connected to a VCM coil 56 provided at a rear end portion 57 of an actuator 40, and a sleeve 70 for insulation is formed on the connected portion. The lead wire 71 is diverged from a flexible printed circuit. The lead wire 71 transmits an electrical signal, which is outputted from a controller (not shown) of the HDD, to the VDM coil 56. Power is accordingly applied to the VCM coil 56, whereby a driving force for the actuator 40 is generated.
In the conventional HDD, a space between the actuator 40 and a cover plate provided over the actuator 40 is narrower than a space between the actuator 40 and a base plate 10 provided under the actuator 40. This space structure makes it important to make efficient use of a space in the small mobile HDD. Due to such a space restriction, the lead wire 71 is connected to the actuator 40 through a soldering technique. In the soldering technique, after a sheath of an end portion (to which the actuator is to be connected) of the lead wire 71 is removed using chemicals such as sulfuric acid, the sheath-removed end portion of the lead wire 71 is plated with tin for easy soldering.
However, the sheath-removing process needs a lot of time because it is manually performed. Also, the tin-plating process is dangerous for a worker because it includes a step of dipping the sheath-removed end portion into hot tin plating bath of 200° C. or above. Further, during the tin-plating process, the hot tin plating bath is undesirably pulled up along the lead wire 71 by its surface tension to thereby burn an unremoved sheath of the lead wire 71. Furthermore, the hot tin plating bath may splash against the unremoved sheath of the lead wire 71, whereby undesirable splashes may remain on the unremoved sheath.
Ashes caused by the above burning and splash results in the pollution of the interior of an assembled HDD. Moreover, when the splashes penetrate the sheath of the lead wire 71, an electrical short may be induced by the contact of the penetrated splashes. The induced electrical short deteriorates the reliability of the HDD.
Accordingly, there is required an improved method for connecting the lead wire 71 to the actuator 40.